1. Field of the Invention
This invention relates to on-line monitoring of moisture in HCl gas and copper in NH.sub.4 solutions.
2. Brief Description of the Prior Art
There is presently no known technique for monitoring moisture contamination in corrosive gas distribution systems, or for monitoring metallic contamination and principally copper contamination in chemical distribution systems or process baths, without extracting a sample from the system and then performing a laboratory analysis of the extracted sample. It follows that considerable delay can occur between the time the contamination occurs and the time it is discovered since there is no way of knowing that such contamination has occurred at the time of such occurrence. In the past, the discovery of such contamination has generally been indirect, resulting from a physical observation of a diminution in wafer yield in semiconductor processing procedures in either of the above noted situations, or from discovery of corrosion in the distribution system itself in the case of moisture contamination. It is therefore apparent that a system which can detect the above noted problems on-line would provide a great economic advantage.